The present invention relates to an interlaced progressive conversion (which will hereinafter be abbreviated to a de-interlace process) technology used when displaying a picture transmitted as carried on interlaced signals based on NTSC (National Television Standards Committee) and PAL (Phase Alternating Line) with a non-interlaced receiver typified by a plasma display and a liquid crystal display.
The de-interlace process has hitherto employed a motion adaptive technology and a motion compensated technology, which detect a motion of the picture and generate interpolation pixels based on this motion. These technologies are based on a premise that in the case of, e.g., NTSC signals, an original picture is an interlaced picture having a time resolution for every 1/60 sec (which will hereinafter also be referred to as 60i (60 frames/s interlace)).
On the other hand, the picture using a [frame] such as a film material of a movie and animation and a CG (Computer Graphic) material generated by a computer, is subjected to so-called telecine conversion involving 2:3 pulldown and 2:2 pulldown and is thus transmitted as carried on interlaced video signals. For instance, if the signals are video signals for transmitting the progressive picture (frames) at a framerate of 24 fps, one frame is allocated into 2 or 3 fields by the 2:3 pulldown. Further, if the signals are video signals for transmitting the progressive picture (frames) at a framerate of 30 fps, one frame is allocated into 2 fields by the 2:2 pulldown.
When the telecine-converted video signals are processed by the interpolation technology such as the motion adaptive technology and the motion compensated technology, lines in the frame where none of the video signal exists are compensated by interpolation data, resulting in occurrence of a problem such as flicker, jaggy and artifact.
As to the telecine-converted videos signals, if a video transmission sequence such as the 2:3 pulldown sequence and the 2:2 pulldown sequence is simply known, the original progressive picture can be restored from the segmented fields.
Hence, there is proposed a converting device that judges whether or not the inputted video signals are the telecine-converted signals, and executes a converting process corresponding to a result of this judgment. FIG. 1 is a schematic diagram of the converting device including a sequence detecting unit 101, a inverse telecine unit 102, and a motion-compensated type de-interlacing unit 103.
The sequence detecting unit 101 compares the respective fields of the inputted video signals, and thus detects the video transmission sequence such as the 2:3 pulldown sequence and 2:2 pulldown sequence or a sequence other than these sequences. If the video information is of the 2:3 or 2:2 pulldown video transmission sequence, the sequence detecting unit 101 notifies the inverse telecine unit 102 of the video transmission sequence, wherein the de-interlace process based on the video transmission sequence is conducted, and the video signals are thus outputted.
Then, the sequence detecting unit 101, when judging that the inputted video information is not of the 2:3 or 2:2 pulldown video transmission sequence, selects and outputs the signals by the de-interlacing unit 103 on the basis of the interpolation technology such as the motion adaptive technology and the motion-compensated technology.
Further, a technology disclosed in, e.g., the following Patent document 1 is given as the prior art related to the invention of the present application.    [Patent document 1] Japanese Patent Application Laid-Open Publication No. 2005-102191